Incidence of erectile dysfunction treatment after radical prostatectomy by Statin use in Finnish Nationwide Cohort Study.

BACKGROUND: Erectile dysfunction (ED) is common after radical prostatectomy (RP) due to cavernous nerve damage. Risk of ED is also affected by vascular function. Statins prevent vascular events but their association with post-prostatectomy ED is unclear. We explored the likelihood of starting ED treatment after RP by statin use at the population level. METHODS: The study cohort included 14,295 prostate cancer (PCa) patients with no ED treatment prior to diagnosis of PCa treated with RP in Finland during 1995-2013. Information on use of cholesterol-lowering drugs and ED medication during 1995-2014 and penile prosthesis implantation during 1996-2014 were gathered from national registries. Risk of ED treatment initiation after RP was analyzed by pre-diagnostic and post-diagnostic statin and non-statin cholesterol lowering (NSCL) drug use with Cox regression model. RESULTS: Pre-diagnostic statin use or NSCL drug use overall had no association with risk of ED treatment initiation after RP. Post-diagnostic statin use was associated with a slightly increased risk of initiation of any ED treatment (HR = 1.07; 95% CI = 1.01-1.14). Patients with the longest duration of post-diagnostic statin use had a significantly decreased risk of PDE5 inhibitor initiation compared to non-users (HR = 0.43; 95% CI = 0.20-0.94). Among patients with no cardiovascular comorbidities, pre-diagnostic statin users had a significantly increased risk of initiation of injectable ED drugs (HR = 1.27; 95% CI = 1.04-1.55), however, no association with risk of any other ED treatment was observed. CONCLUSION: Statin users have a slightly increased risk of ED treatment initiation after RP, which probably reflects the effect of the underlying vascular insufficiency.

Prostate Cancer-specific Survival After Radical Prostatectomy Is Improved Among Metformin Users but Not Among Other Antidiabetic Drug Users.

BACKGROUND: Metformin has been linked to improved survival among diabetic prostate cancer (PCa) patients, while hyperinsulinemia and insulin usage has been related to worse prognosis. OBJECTIVE: To evaluate the association of metformin and other antidiabetic drugs with PCa death and androgen deprivation therapy (ADT). DESIGN SETTING AND PARTICIPANTS: The study cohort included 14 424 men who underwent radical prostatectomy in Finland during 1995-2013. Cases were identified, and clinical data were collected from patient files and national registries using personal identification numbers. INTERVENTION: Information on the use of each antidiabetic drug during 1995-2014 was collected from prescription registry of the Social Insurance Institution of Finland. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The risks of PCa death and initiation of ADT were analyzed by antidiabetic drug use with the Cox regression method. Each antidiabetic drug group was analyzed separately to model simultaneous usage. Pre- and postdiagnostic uses were analyzed separately. RESULTS AND LIMITATIONS: Prediagnostic use of antidiabetic drugs in general had no association with the risk of PCa death. Prediagnostic use of metformin was related to a reduced risk of ADT initiation (hazard ratio [HR] 0.75, 95% confidence interval [CI] 0.59-0.96), while high-dose insulin users had an increased risk. Overall, antidiabetic drug use after PCa diagnosis was associated with an elevated risk of PCa death. Only postdiagnostic metformin use was associated with reduced risks of PCa death (HR 0.47, 95% CI 0.30-0.76) and ADT initiation compared with nonusers. Study limitations are missing information on glycemic control, smoking, living or exercise habits, prostate-specific antigen, and Gleason score. CONCLUSIONS: Among surgically treated PCa patients, use of metformin was associated with improved disease-specific survival, while insulin and insulin secretagogues were associated with poor survival. Metformin might be a favorable diabetes treatment among men with PCa. PATIENT SUMMARY: In this Finnish nationwide study, we found that the risks of prostate cancer death and cancer progression are lowered among metformin users, but not among other antidiabetic drug users. Metformin might be a favorable treatment choice for diabetes in men with prostate cancer.

Prostate cancer survival among statin users after prostatectomy in a Finnish nationwide cohort.

BACKGROUND: Improved prostate cancer (PCa) survival by statin use has been reported among PCa patients managed with radiation or androgen deprivation therapy (ADT), while results are controversial for men managed surgically. We evaluate the association between cholesterol-lowering medication with initiation of ADT and disease-specific death among PCa cases who underwent radical prostatectomy in Finland between 1995 and 2013. METHODS: The study cohort included 14 424 men with PCa who underwent radical prostatectomy in Finland between 1995 and 2013. Cases were identified from national hospital discharge registry. Clinical data were amended from patient files of the treating hospitals. Information on co-morbidities, additional radiation- or chemotherapy, and causes of deaths were collected from national registries. Personal-level data on medication use during 1995-2014 were gathered from national prescription database. Registry linkages were carried out using personal identification number. Lipid-lowering drugs were categorized into statins and non-statin drugs. Risk of PCa death and initiation of ADT was analyzed using Cox-regression model with adjustment for age, radiation therapy, chemotherapy, co-morbidities and other drug use. Statin use was analyzed as time-dependent variable. Delayed risk associations were evaluated in lag-time analysis. RESULTS: Compared to non-users the risk of PCa death was significantly lower among statin users before PCa diagnosis (HR 0.70, 95%CIs 0.52-0.95). For statin use after PCa diagnosis the risk was lowered in age-adjusted analysis (HR 0.76 95%CIs 0.62-0.93) but not after multivariable-adjustment. Post-diagnostic statin use was associated with improved PCa-specific survival in 1, 3 and 5 years lag-time analyses. The risk reduction was clearest for statin use initiated 5 years earlier (HR 0.71 95%CIs 0.55-0.92). Use of statins both before and after PCa diagnosis was associated with reduced risk of ADT use (HR 0.72 95%CIs 0.65-0.80 and HR 0.73, 95%CI 0.67-0.80, respectively). The risk of ADT decreased by increasing intensity of statin use before diagnosis. CONCLUSION: Statin use among surgically treated PCa patients has significant association with decreased risk of starting ADT and PCa death. The risk is lowered especially among men with statin use before PCa diagnosis and in men who used statins at high-dose. Our results are hypothesis generating due to retrospective study design.